1. Field of the Invention
This invention in general pertains to food products prepared in cooking oil or oil substitutes and concerns more particularly an improved method and apparatus for frying products especially battered and breaded products in a manner whereby the breaded coating remains substantially intact as the product is conveyed continuously through the frying system.
A number of successfully marketed food products, chicken, beef, fish, filled dough, vegetables, etc. are prepared by coating or battering the product and covering the coating with bread crumbs or the like and frying thereafter. During the frying step in which the product is either partially or fully cooked, it is highly desirable that as much of the breading or other coating be retained on the product and that a very minimum of the coating slough off into the cooking oil. When particles of the coating break away from the product, this results in a lower production yield and the fines sloughed off contaminate the frying oil. These breading and product fines must be removed from the frying medium on a regular basis to avoid degrading the cooking oil to a point where it must be supplemented by a higher quality oil or else removed for recycling. This event places a high economic burden on control of the cooking oil as well as control on the battered and breaded product. Maintaining a balance between product yield and oil quality has been a challenge which faced food processors over a long period of time. This is true of non breaded and battered products as well.
2. Description of the Prior Art
Prior art equipment and techniques were developed in attempts to minimize the removal of breading or other coatings from the underlying food product. In the conventional hot oil cooking fryer substantial turbulence or "boil" is generated when the relatively cold uncooked food product is dropped into the hot cooking oil. This turbulence contributed to removal of portions of coatings and continued to a lesser degree as the product is conveyed through and cooked in the hot oil bath. To overcome this undesirable effect food processors turned to cooking the products in batch cookers where the relative motion between the product and the cooking oil would be quite low, although the initial turbulence or "boil" was always present. Other procedures involved cooking in ovens after applying an oil spray coating as a preparatory step to the oven cooking. Gentle handling of the coated product while cooking was a desired goal but rarely achieved to complete satisfaction for high product yields with high production output.
It is highly desirable to minimize the relative motion between the bread and battered product and the cooking medium, whether the cooking medium is cooking oil or processed cooking vapor. This is evident because a rapidly moving cooking medium is more than likely the cause of portions of the bread coating to be removed from the product which thereby reduces the yield on the one hand and produces contamination of the cooking medium on the other.
Where the choice is made to cook a breaded and batter product in cooking oil there are substantial advantages in using the minimum practical amount or volume of cooking oil. However where the product fryer has a large bath of cooking oil, the large air-oil surface and the consequent exposure of the cooking oil to air causes the oil to degrade. Replacement of the complete oil bath or make-up oil must be supplied to maintain or uphold the desired cooking oil quality. Should the oil degrade significantly, there will be caused an "off taste" to be imparted to the product. This must be guarded against to avoid product rejection for quality control reasons as well as to postpone the costly replacement of the degraded oil. In the prior art use of a reduced volume of cooking oil has been thought to be impractical where high product output is the goal.